Taurine (2-aminoethanesulfonic acid) is a natural organic acid present in many animal organisms. Taurine is essential to the healthy maintenance of skeletal muscle, cardiovascular function, and central nervous system function. It is also an anti-oxidant and it helps stabilize cellular membranes.
Over the last 15 years, taurine and taurine derivatives have been used in a variety of cosmetic and personal care compositions, including hair conditioners, moisturizers, cleansing products, shaving cream and after-shave compositions. Taurine is suspected to have anti-fibrotic properties and has been shown to protect hair follicles from damage caused by the transforming growth factor family of proteins. Taurine also helps maintain skin hydration, contributing to the healthy maintenance of the skin barrier, and helps reduce inflammation and/or irritation of the skin.
Most of the cosmetic and personal care products that contain taurine are non-solid compositions, such as gels, creams, lotions, and liquids. In attempting to formulate a solid cleansing bar composition containing taurine, the inventors have found that under normal aging conditions (e.g., dry room temperature aging), gritty solid particles or crystals of taurine precipitate out of the composition on its surface. This gives the cleansing bar an unwelcome abrasive feel. Consequently, there is a need for formulating cleansing soap bars that deliver the beneficial effects of taurine without undesirable precipitation of taurine on the surface.